Nope. Not photoshop. It looks 99% like that on the back of my camera.
That would really be a lot of work to do in post and I'm not that industrious.

I used a flash off camera-left. It has a 1/2 blue gel, coloring the light. The camera's white balance is set to shade (which gives direct sunlight a warm tint, and makes the blue light look white). I adjusted the white balance a tiny bit off from the camera's preset to make even the blue light look warm.
There was some post processing, like making the flower a little lighter, but not that much. Nothing time consuming like merging separate images.

And thank you to ycysuscan2001 for making such a cool costume and for putting up me fussing with settings for awhile to get that balance worked out. Also thanks to the person who held the flash.

This is very pretty... you can kinda tell it's been photoshopped because the lighting in the background is not consistent with the lighting on the costume... especially on the face... but none the less good composition.